You'd literally would have to have the shell of that W211 Mercedes and swap over every single electronic bit.

W210's are notorious for lack of electronic parts interchange, the W211's have to be worse.

Just buy a wrecked W211 and go to town.

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.